Dear Drumheads. I wrote two small patches for Hydrogen previously. With a classical "scratch your own itch" approach to development, I would like try fixing some of the problems that I'm having using the program, but are not on the roadmap that Alex laid out. Perhaps it seems like I'm taking my hands too full --- but really, I don't think It's that bad, *and* if I could get it to work, it'd be dead cool (H)
I'll need some tips along the way though, and it would be nice to get feedback before I start to write code! Here's what it's all about: My first interest in Hydrogen is the timing and synchronization with other JACK apps --- Ardour is, of course, the first reference when it comes to JACK, and another one I really want to use together with Hydrogen is Freewheling ( a wierd / wonderful live looping application ). The first patch I wrote for Hydrogen already made it possible to accept changes in tempo and song position from the JACK transport system, and that seems to work o.k. right now, at least with Ardour. Along the same line, I would like to try to enable Hydrogen to *send* these messages to other JACK apps ( in JACK, an application can be either `slave' or `timebase master'. Hydrogen acts as `slave' when the `Jack Transport' button is active, and I would like to add a `master' option as well ) but this is when I get into some problems that I think have to do with the *fundamental design of the timeline* in Hydrogen, and, as far as I can tell, the internal representation of this timeline will have to change fundamentally, in order for me to succeed in adding the extra option... The problem is that Hydrogen doesn't really know the length of a `bar'... It just knows the Patterns and PatternGroups. The latter are collections of Patterns that start at the same time, and they are the columns in the "song editor" part of the UI. If every pattern is 4 beats long, and the song is in 4/4, it works great, and the PatternGroups are the barlines --- I'm guessing this is what happens in 95% of the use cases. The trouble start when: * Patterns of different length are inserted in the same PatternGroup. Then the behaivour of the program seems a bit random... It doesn't crash or make ugly noise, but some patterns are cut off, or silence is inserted, somehow. * If there is a two-bar pattern in one PatternGroup, and a one-bar pattern in the next, the two-bar pattern only takes up one `bar' in the UI, which, I think, seems illogical and buggy... To remedy all this, I *just about* figured out a way of storing the starting times of patterns in a song in a way that it's o.k. if patterns are not the same length, and one pattern can start in the middle of another one playing. AND the sequencer will know which notes / patterns to play at any given time. When I start messing with all this, the entire program will of course stop working at first, and It'll have to be repaired everywhere where the timeline information is accessed... What I fear the most is the parts of the program that I *don't know* interact with the timeline. I foresee trouble in these three places: 1. The UI, where patterns are inserted into the song 2. The Sequencer, that plays each note from each pattern in the song and 3. The file format writer and reader, that also need to know the song structure!! I want to know if I missed any? I also wonder if anyone is up to attacking this, or at least giving me some hints -- I guess there are plenty of other things to do before the long-awaited 9.4 release!! I think that making the changes I suggest could make Hydrogen a more musical program, and also make the code easier to maintain, and maybe even faster. Well, think about it anyway, and have fun ;-) see you Jakob Lund, Ollerup, Denmark. ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Hydrogen-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/hydrogen-devel
